President Trump pushed back on former FBI Director James Comey's explanation for a recent social media post that appeared to call for a hit on the president's life, saying, "He knew exactly what that meant."

Comey has since deleted the Instagram post he shared Thursday that showed the numbers "86 47" etched in the sand at a beach via seashells. The numbers are perceived as a call to "86" the 47th president, which is used as a call sign for murder. And he attempted to walk back the post, which he originally captioned "Cool shell formation on my beach walk," by stating he was unaware of the violent message behind the numbers. 

"I posted earlier a picture of some shells I saw today on a beach walk, which I assumed were a political message," Comey's follow-up post read on Thursday. "I didn't realize some folks associate those numbers with violence. It never occurred to me but I oppose violence of any kind so I took the post down."

Homeland Security Secretary Kristi Noem on Thursday evening confirmed that the Secret Service and her department are investigating the post.